Explosive



UNITED STATES PATENT oirrrcia.

FREDERICK MARK IBECKE'I', OF NIAGARA ELECTED METALLURGICAL COMPANY, OF ACORPORATION OF WEST VIRGINIA.

EXPLOSIVE.

No Drawing.

To all whom it may concern: f

Be it known that we, (1) JOHN R. MAR- DICK and (2) FREDERICK M. Bnonn'r,(1) acitizen of the United States and (2) a subject of the King of GreatBritain, residing at (1) New York, (2) Niagara Falls, in the counties of(1) New York, (2) Niagara, and State of New York, have invented new anduseful Improvements in Explosives, of which the following is aspecification.

This invention relates to certain novel explosive compositions suitablefor blasting and other commercial purposes, and con taining as essentialcomponents one or more normally solid nitro-aromatic bodies having atleast three nitro-groups, of which trinitro-toluol (T. N. T.) and picricacid are types, associated with an oxidizing agent or agents and amagnesium-silicon alloy.

A general formula for an explosive composition embodying-our inventionis as follows Combustible O- 5)? by weight Plasticizing ingredient" 1 5%by weight Anti-acid 0 1']? by weight An illustrative formula for acommercial (blasting) explosive of the plastic type, capable of beingtamped into place. is as follows Picric acid or T. N. '1 1TMagnesium-silicon alloy 10 "0 Ammonium nitrate 35 {-T/p Sodium nitrateDinitrotoluol 3 \Vood flour 3 7 Calcium carbonate 0.5% Each of theessential components of the explosive, performs a function in themixture. and the. proportions of the components will be varied inpractice as may be necessa to the proper performance of this function,having in view the specific puppose for which the explosive is intended.I

The nitro-aromatic bodies are normally solid but readily fusible, andare therefore easily compounded with the other ingredients, yieldingcohesive plastic compositions which are readily tamped into conformitySpecification of Letters Patent.

Application filed June 19,

Patented Apr.6,1920.

1918. Serial No. 240,793.

to the bore. Instead of T. N. T. or picric acid I may use othernitro-aromatic bodies having similar desirable qualities, as for exampletriand tetra-nitro-naphthalene, and the tri-nitro cresols,

The oxidizer is in sufiicient proportion to convert any carbon monoxidinto carbon dioxid and serves in general to oxidize all poisonous orobjectionable gases or compounds, rendering the products of explosioninnocuous. It is also used in sufficient excess to etfect oxidation ofthe paraflined paper wrapper usually employed. The wood flour or othercombustible will unite with any otherwise unconsumed excess of theoxidizing component. The use of the antiacid body is precautionary,guarding against development from any cause of an acid condition in themixture.

In case a hygroscopic salt such as ammonium nitrate is used I prefer tointroduce into the mixture small proportions, say four per cent. orless, of a. liquid capable of coating the salt-and thereby protecting itfrom atmospheric moisture. For this purpose I may use Vaseline, oils,etc.; but I prefer liquid nitro bodies such for example as the -liquidnitro xylenes, o-dinitro benzene, di-

nitro toluene or the like. These liquid nitro bodies act as deadeninagents, and therefore should not be used in excessive proportions.

A primary advantage 'of the introduction of magnesium into explosivemixtures fol lows from the great amount of heat liberated in course ofits combination with oxygen. Magnesium metal however particularly whenvery finely subdivided and when existing under the conditions obtainingin the explosive mixture, is somewhat lacking in stability and liable toslow oxidation. It has been found on the other hand that themagnesium-silicon alloys are sufiiciently stable to permit of such use.In this respect the magnesium-silicon alloys are sharply differentiatedfrom such alloys as those of silicon with calcium. For example calciumsilicide corresponding substantially to the formula CaSi is a tairlstable compound, but alloys of calcium and silicon containing amaterially higher proportion of calcium than the above are conimratively unstable; consequently it has not proven practicable toincrease the power of explosive mixtures sufficient stability containingcalcium and silicon by increasing the calcium content of the alloycomponent. This does not apply however to the magnesium-silicon alloys,which possess a sulficient degree of stability for the purposes1ndicated even when the magnesium content is decidedly higher thancorresponds to the known silicide MgSi. Such compounds, 1

respective of the presence or absence of iron or other components, maybe defined as alloys in which the magnesium is in excess of theequimolecular con.

A further advantage in the use of magnesium-silicon alloys arises asfollows The magnesium component of the alloy requires for its oxidationonly about one-half of the oxygen required by the silicon component. Itfollows from this that the higher the relative proportion of magnesiumin the alloy, the larger the permissible proportion of the alloy in theexplosive mixture. It is therefore of great advantage in this connectionthat the magnesiumsilicon alloys containing more than the equimolecularproportion of magnesium possess for use in explosive comproportion tothe silipositions.

Other advantages arising from the use of magnesium-silicon alloys incompositions of the kind above indicated follow from the relativelightness of these alloys and from the fact that the alloys arerelatively brittle as compared with metallic magnesium, and are hencemore easily pulverized to the requisite degree of fineness. I It will ofcourse be understood that it is Within our invention to use-silicon inother reduced forms, for example as ferro-silicon, in conjunction withor in part replacement of the magnesium-silicon alloys. For example ourinvention contemplates the complete or partial replacement of.ferro-silicon by magnesium-silicon alloys in such formulae as aredisclosed in the copending application of John R. Mardick, Serial No.207,389, filed December 15, 1917. Nor is our invention restricted to theuse of magne sium-silicon alloys in which the magnesium tro-body, and

exists in higher proportions to the silicon than the equimolecularproportion; although we prefer in all cases to use alloys containingsuch higher proportions of magnesium.

' We claim v l. A commercial explosive containing nitro-aromatic' body,an oxidizer, and magnesium-silicon alloy.

2. A- commercial explosive containing a nitro-aromatic body, anoxidizer, and a magnesium-silicon alloy in which the magnesium is inexcess of the equimolecular proportion to the silicon.

3. A commercial explosive containing a nitro-aromatic body having atleast three nitro-groups, an oxidizer, and a magnesiumsilicon alloy.

4:. A commercial explosive containing a nitro-aromatic body having atleast three nitro-groups, an oxidizer, and a magnesiunr silicon alloy inwhich the magnesium is in excess of the equimolecular proportion to thesilicon.

5. A commercial explosive containing a nitro-aromatic body having atleast three nitro-groups, an oxidizer, a plasticizing ingredient, andamagnesium-silicon alloy.

6. A commercial explosive containing a -n itro-aromatic body having atleast three intro-groups, an oxidizer, a plasticizing ingredient, and amagnesium-silicon alloy in which the magnesium is in excess of theequimolecular proportion to the silicon.

7. A commercial explosive containing a nitro-aromatic body having atleast three nitro-groups, an oxidizer, a plasticizing niamagnesium-silicon alloy. 8. A commercial explosive containing anitro-aromatic body having at least three nitro-groups, an oxidizer, aplasticizing nitro-body, and a magnesium-silicon alloy in which themagnesium is in excess of the equimolecular proportion to the silicon.

In testimony whereof, we aflix our signatures.

JOHN R. MARDICK. FREDERICK MARK BEGKET.

